Under the iTunes in the Cloud section, click Manage Devices. (If you haven't associated any devices with your Apple ID, you won't see the Manage Devices section.) Information about each associated device appears. Next to each device, you can see when it associated with your Apple ID.
The real reason why the burp smells so badly is hydrogen sulfide (H2S). If you eat foods that have sulfur proteins in them then you may find yourself burping the H2S, which will smell like rotten eggs. The sulfur reducing microbes in the intestine digest the proteins and release the gas.
Persistent belching could be a sign of digestive conditions that require medical treatment. Some examples are delayed gastric emptying (gastroparesis) and peptic ulcer disease (painful sores in the stomach lining). Gallstones and gallbladder problems can, in some cases, cause symptoms such as belching. Even more rarely, cancer of the stomach or the oesophagus can explain the severe burping. If the burping is persistent and accompanied by symptoms such as nausea, pain, bloody stools, weight loss or fever, you should consult a doctor. 7 tips to prevent excessive belching and burping